NEWDIA "SS000005.SIT",YCALLOUT -2.206687e-01,-3.099280e-01,-2.206687e-01,-3.099280e-01,ffff00,80000000,40ffffff,ffffffd0,0,0,0,2bc,ff,22010203,61697241,6c,0,0,0,0,0,0,The Motion of StarsPAUSE 7 sDELCALLOUT The Motion of tarsPAUSE 1 sCALLOUT -4.115155e-01,-1.497985e-01,-4.115155e-01,-1.497985e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,2072006c,77654e,0,0,0,0,0,In ancient times, stars were thought to bemotionless and immutable, and they werecalled "fixed stars".PAUSE 1 sCALLOUT -4.106546e-01,-8.178655e-02,-4.106546e-01,-8.178655e-02,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,2072006c,77654e,0,0,0,0,0,Modern astronomical instrumentsshowed us that this is not true.PAUSE 1 sCALLOUT -4.106546e-01,-3.185371e-02,-4.106546e-01,-3.185371e-02,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,2072006c,77654e,0,0,0,0,0,Stars move with respect to each other.But to see the effect with the naked eye,you should wait for thousands years...CALLOUT -3.589999e-01,1.179448e-01,-3.589999e-01,1.179448e-01,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYDELCALLOUT Press PgDn to continue...DELCALLOUT In ancient times, stars were thought to be motionless and immutable, and they were called "fixed stars".DELCALLOUT Modern astronomical instruments showed us that this is not true.DELCALLOUT Stars move with respect to each other. But to see the effect with the naked eye, you should wait for thousands years...CALLOUT -3.942973e-01,1.136403e-01,-3.942973e-01,1.136403e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,2072006c,77654e,0,0,0,0,0,Now you are looking at the constellation of theGreat Bear: in particular, you can see clearlythe seven-stars asterism of the "Great Dipper".Now the time will be accelerated so that 100,000years will be gone in twenty seconds.CALLOUT -3.667481e-01,2.195323e-01,-3.667481e-01,2.195323e-01,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to start...WAITKEYDELCALLOUT Press PgDn to start...DELCALLOUT Now you are looking at the constellation of the Great Bear: in particular, you can see clearly the seven-stars asterism of the "Great Dipper". Now the time will be accelerated so that 100,000 years will be gone in twenty seconds.PAUSE 1 sNEWDIA "SS000004.SIT",YCALLOUT -5.272699e-02,1.406053e-01,-5.272699e-02,1.406053e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0, 2000ADPAUSE 1 sMOVIE CONT,5000y,1 s,0.6s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 2000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0, 5000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 5000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,10000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 10000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,15000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 15000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,20000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 20000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,25000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 25000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,30000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 30000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,35000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 35000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,40000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 40000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,45000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 45000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,50000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 50000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,55000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 55000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,60000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 60000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,65000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 65000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,70000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 70000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,75000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 75000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,80000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 80000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,85000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 85000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,90000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 90000ADCALLOUT -5.330761e-02,1.400874e-01,-5.330761e-02,1.400874e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,95000ADMOVIE CONT,5000y,1 s,1s,SIMTIME,PRESERVECALLOUTS,SINGLEDELCALLOUT 95000ADCALLOUT -5.337649e-02,1.403285e-01,-5.337649e-02,1.403285e-01,ffff00,80000000,c0ffffff,fffffff0,0,0,0,2bc,0,31010203,72756f43,20726569,77654e,0,0,0,0,0,100000ADCALLOUT -9.728295e-02,1.997314e-01,-9.728295e-02,1.997314e-01,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYDELCALLOUT 100000ADDELCALLOUT Press PgDn to continue...CALLOUT -4.356210e-01,-2.556906e-01,-4.356210e-01,-2.556906e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,The motion we have seen is the consequenceof the motion of all stars (included our Sun)orbiting around the centre of our Galaxy.PAUSE 1 sCALLOUT -4.364819e-01,-1.894004e-01,-4.364819e-01,-1.894004e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Our Galaxy is a spiral. The orbits of itsstars lie near a plane, called "GalacticPlane", around the nucleus.SHOWJPG 3.719136e-03,-2.268673e-01,3.719136e-03,-2.268673e-01,40000000,galaxy.jpgCALLOUT 1.911223e-01,-5.251557e-02,1.343021e-01,-1.248321e-01,ffff00,80000000,40ff0000,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,The Sun is in the outer part of onespiral arm of our Galaxy.PAUSE 1 sCALLOUT -4.356210e-01,-1.162230e-01,-4.356210e-01,-1.162230e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Each star travels at a different velocity. Butthis is different from the situation of our SolarSystem, where planets near to the Sun movefaster than planets far from the Sun, followingthe third Kepler's law. In our Galaxy, the matteris not concentrated in the centre, so the orbitalvelocity increases from the centre up to a pointwhere it becomes about constant and thendecreases.PAUSE 1 sPAUSE 1 sCALLOUT -4.364819e-01,6.887289e-02,-4.364819e-01,6.887289e-02,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,The Sun has a velocity of about 250 km/s in itsgalactic orbit. The stars near to the Sun usuallyshow relative velocities of tens of km/s.CALLOUT -3.813836e-01,1.446331e-01,-3.813836e-01,1.446331e-01,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYDELCALLOUT C:\BC4\ASTRO95\SCRIPT\galaxy.jpgDELCALLOUT The motion we have seen is the consequence of the motion of all stars (included our Sun) orbiting around the centre of the Galaxy.DELCALLOUT Our Galaxy is a spiral. The orbits of its stars lie near a plane, called "Galactic Plane", around the nucleus.DELCALLOUT The Sun is in the outer part of one spiral arm of the Galaxy.DELCALLOUT Each star travels at a different velocity. But this is different from the situation of our Solar System, where planets near to the Sun move faster than planets far from the Sun, following the third Kepler's law. In the Galaxy, the matter is not concentrated in the centre, so the orbital velocity increases from the centre up to a point where it becomes about constant and then decreases.DELCALLOUT The Sun has a velocity of about 250 km/s in its galactic orbit. The stars near to the Sun usually show relative velocities of tens of km/s.DELCALLOUT Press PgDn to continue...CALLOUT -4.373428e-01,-2.556906e-01,-4.373428e-01,-2.556906e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,2072006c,77654e,0,0,0,0,0,Some stars don't orbit near to the GalacticPlane. They are stars from the so-called"Galactic Halo". So their velocity relative tothe Sun is greater, and the effects of theirmotion is visible in a shorter time span.PAUSE 1 sCALLOUT -4.364819e-01,-1.437721e-01,-4.364819e-01,-1.437721e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,2072006c,77654e,0,0,0,0,0,Now we will see an example.CALLOUT -4.218464e-01,-9.642204e-02,-4.218464e-01,-9.642204e-02,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYNEWDIA "SS000000.SIT",YCALLOUT -8.005765e-03,-4.822370e-03,-8.005765e-03,-4.822370e-03,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,The Barnard's star is the second neareststar, at six light years only.PAUSE 1 sSHOWJPG -2.037322e-04,1.878864e-03,-2.037322e-04,1.878864e-03,40000000,frecciaverde.jpgPAUSE 7 sCALLOUT -7.990006e-03,-3.750732e-03,-7.990006e-03,-3.750732e-03,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,It is too faint to be seen with the nakedeye, but it can be observed with a smalltelescope.PAUSE 7 sCALLOUT -7.974246e-03,-2.379666e-03,-7.974246e-03,-2.379666e-03,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,Let's see how it moves in 50 years:PAUSE 5 sMOVIE CONT,5y,1 s,10 s,SIMTIME,PRESERVECALLOUTS,SINGLESHOWJPG -9.054766e-05,-7.243813e-04,-9.054766e-05,-7.243813e-04,40000000,1_frecciaverde.jpgCALLOUT 1.733532e-03,0.000000e+00,1.733532e-03,0.000000e+00,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,The other stars visible here are muchfarther away, and appear to be motionless.PAUSE 1 sCALLOUT 1.765051e-03,1.071638e-03,1.765051e-03,1.071638e-03,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,No star appears to move faster than theBarnard's star. This is due to its vicinity,with the fact that its motion has a completelydifferent direction from the direction of the Sun.CALLOUT 2.474223e-03,3.608898e-03,2.474223e-03,3.608898e-03,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYNEWDIA "SS000002.SIT",YSHOWJPG -2.037322e-04,1.878864e-03,-2.037322e-04,1.878864e-03,40000000,frecciaverde.jpgSHOWJPG -9.054766e-05,-7.243813e-04,-9.054766e-05,-7.243813e-04,40000000,1_frecciaverde.jpgPAUSE 1 sCALLOUT 2.521501e-03,3.750732e-03,2.521501e-03,3.750732e-03,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,You can compare the motion of theBarnard's star in 50 years with theapparent size of the MoonPAUSE 1 sNEWDIA "SS000006.SIT",YCALLOUT 2.521501e-03,3.750732e-03,2.521501e-03,3.750732e-03,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,You can compare the motion of theBarnard's star in 50 years with theapparent size of the MoonSHOWJPG -2.037322e-04,1.878864e-03,-2.037322e-04,1.878864e-03,40000000,frecciaverde.jpgSHOWJPG -9.054766e-05,-7.243813e-04,-9.054766e-05,-7.243813e-04,40000000,1_frecciaverde.jpgCALLOUT 3.025801e-03,4.901167e-03,3.025801e-03,4.901167e-03,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYNEWDIA "SS000020.SIT",YCALLOUT -4.943201e-01,-3.133289e-01,-4.943201e-01,-3.133289e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,Now we are observing Sirius,the brightest star in the sky.CALLOUT 6.811498e-03,-2.238064e-02,6.811498e-03,-2.238064e-02,ffffff,0,40ffffff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,0,0,0,0,0,0,SiriusPAUSE 10 sCALLOUT -4.962663e-01,-2.549446e-01,-4.962663e-01,-2.549446e-01,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,Sirius is slightly farther than the Barnard's Star,but it is a star of the Galactic Disc, like our Sun,so its apparent motion is six times smaller.CALLOUT -4.505319e-01,-1.479068e-01,-4.505319e-01,-1.479068e-01,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYNEWDIA "SS000021.SIT",YCALLOUT -7.342106e-04,-4.467972e-04,-7.342106e-04,-4.467972e-04,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,Observed with a telescope, Sirius appearsto be a double star, with a faint companion.PAUSE 1 sCALLOUT -7.302913e-04,-3.657989e-04,-7.302913e-04,-3.657989e-04,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,These two stars are bound by thegravitational force: while movingin space, they orbits around theircentre of gravity.CALLOUT -6.963243e-04,-2.534464e-04,-6.963243e-04,-2.534464e-04,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to start...WAITKEYDELCALLOUT Press PgDn to start...MOVIE CONT,5y,1 s,20s,SIMTIME,PRESERVECALLOUTS,SINGLEPAUSE 1 sNEWDIA "SS000024.SIT",YCALLOUT -6.897922e-04,-4.481036e-04,-6.897922e-04,-4.481036e-04,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,As a result, the apparent motionof Sirius is not a straight line.PAUSE 1 sCALLOUT -6.649701e-04,2.233986e-04,-6.649701e-04,2.233986e-04,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,In the XIX century, when astronomicalinstruments could not see the companion,its existence was predicted after theobservation of the irregular motion of Sirius.CALLOUT -6.061810e-04,3.801696e-04,-6.061810e-04,3.801696e-04,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYNEWDIA "SS000036.SIT",YCALLOUT 5.578115e-05,-1.944371e-04,5.578115e-05,-1.944371e-04,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,Sirius and its companion orbit around acommon point called the "barycentre" ofthe system, that moves uniformly in space.PAUSE 1 sCALLOUT -1.290935e-04,-1.965621e-04,-8.181235e-05,-1.747809e-04,ffffff,0,40ffffff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,barycentrePAUSE 1 sNEWDIA "SS000035.SIT",YCALLOUT 5.578115e-05,-1.944371e-04,5.578115e-05,-1.944371e-04,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,Sirius and its companion orbit around acommon point called the "barycentre" ofthe system, that moves uniformly in space.CALLOUT -1.290935e-04,-1.965621e-04,-8.181235e-05,-1.747809e-04,ffffff,0,40ffffff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,barycentrePAUSE 1 sCALLOUT 1.062498e-04,-7.065612e-05,1.062498e-04,-7.065612e-05,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,The two stars and the barycentreare always aligned.CALLOUT -9.172988e-05,-1.536475e-04,-7.644157e-05,-1.788733e-04,ffffff,0,408080ff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,CALLOUT -9.631637e-05,-1.123691e-04,-3.974961e-05,-1.138979e-04,ffffff,0,408080ff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,CALLOUT -7.720598e-05,-7.414832e-05,-1.070182e-05,-4.739377e-05,ffffff,0,408080ff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,CALLOUT -3.822078e-05,-2.751896e-05,1.146624e-05,1.605273e-05,ffffff,0,408080ff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,CALLOUT 2.369689e-05,4.204286e-05,2.599013e-05,7.185507e-05,ffffff,0,408080ff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,CALLOUT 4.127845e-05,1.429457e-04,5.580234e-05,1.169556e-04,ffffff,0,408080ff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,CALLOUT -8.026365e-05,-1.727579e-04,5.121585e-05,1.238353e-04,ffffff,0,40ff8040,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,PAUSE 3 sCALLOUT 0.000000e+00,-1.078436e-04,-3.665618e-05,-7.809361e-05,ffffff,0,40ffffff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,the barycentre moves along this lineCALLOUT -1.062498e-05,-1.312185e-04,-3.293744e-05,-1.046561e-04,ffffff,0,40ffffff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,Sirius' trajectoryCALLOUT -2.342808e-04,-9.137483e-05,-8.234360e-05,-7.649986e-05,ffffff,0,40ffffff,fffffff5,0,0,0,2bc,0,22010203,61697241,6c,1a,3,6e,10,202,0,trajectory of the companionCALLOUT 7.703111e-05,-5.206240e-05,7.756236e-05,-5.206240e-05,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to start...WAITKEYDELCALLOUT Press PgDn to start...MOVIE CONT,4y,1 s,12.5s,SIMTIME,PRESERVECALLOUTS,SINGLECALLOUT 1.136873e-04,1.774372e-04,1.136873e-04,1.774372e-04,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to continue...WAITKEYNEWDIA "SS000038.SIT",YCALLOUT -4.857178e-05,-7.228468e-06,-4.857178e-05,-7.228468e-06,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,The barycentre of a system of starsis analogue to the fulcrum of a leverin equilibrium.PAUSE 1 sCALLOUT -4.865993e-05,-9.696725e-07,-4.865993e-05,-9.696725e-07,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,0,0,0,0,0,0,The barycentre is nearer to the more massivestar.PAUSE 1 sSHOWJPG -1.712370e-05,1.078159e-05,-1.712370e-05,1.078159e-05,40000000,1_bilancia.jpgPAUSE 1 sCALLOUT -4.865993e-05,4.495754e-06,-4.865993e-05,4.495754e-06,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,Observing the motion of two stars, youcan determine the mass ratio.PAUSE 1 sCALLOUT -4.856780e-05,9.713560e-06,-4.856780e-05,9.713560e-06,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,This way, the mass of the companion wasdetermined as 2/5 of the mass of Sirius.PAUSE 1 sCALLOUT -4.847949e-05,1.518847e-05,-4.847949e-05,1.518847e-05,ffff00,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,6c,1a,3,6e,10,202,0,If the distance of the system is known, youcan determine the mass of each star. This isthe most fundamental method of measurementof the mass of stars other than the Sun.CALLOUT -1.948160e-05,3.367408e-05,-1.948160e-05,3.367408e-05,ffffff,80000000,40ffffff,fffffff3,0,0,0,190,0,22010203,61697241,7a64006c,3687ffff,3dbdc03a,ffff168f,1c3687,36870000,a74c0177,Press PgDn to end the script...WAITKEYSS000005.SIT:SITUFILE06\ :7/ \ :7/,BA?!Definito dall'utenteʌ j?@F˿c@[gqA1A'@{AL\}t9o.}v=s?4FL?4 ?CX:ݼ,?\wxῦk?ّ????F'pB<7F'>?pn Y>Ȕ75<?kRSZʑ?w?TVp$ǿXR ?lu Ӝ?6P5WY8VZ)3?5Wp+q׿5min0.5 s<^*A?g@rn|?dSS000004.SIT:SITUFILE06 :7/  :7/,BA?!Definito dall'utenteʌ j?@F˿c@[gqA1A'@{AL\}t9o.}v=s?4FL?4 ?CX:ݼ,?\wxῦk?ّ????F'pB<7F'>?pn Y>Ȕ75<?kRSZʑ?w?TVp$ǿXR ?lu Ӝ?6P5WY8VZ)3?5Wp+q׿5min0.5 s<^*A?g@rn|?dgalaxy.jpgFJFIFHHC    ! #'2*#%/%+;,/35888!*=A<6A2785 ",!1"AQa#2q$? R S S S DKbDDD@ 5SH @F3 nJn G UAf=NEhBBXG*ػ8,{y HLn-pEjjٿSMDkQcGh˚hnRWA^cD@l|;_g)d=h_o 9A!ʢF4P'5 GJ"4"5b;#GdH̅T8%wF_Ѳ=pO$& OVX,l?k nƷM !.8!AGcS;^Ul bb670 pRLl'RήGb-;Bw( ߅J? ;XzѳK/<.!, 5 eV2lW捅9ocZ6Z;Ϲ2{@Lk`zTd: "HHUrD5ivoZ<2|/64oW!i 0?p 0[Uə-aN&~z*?F4%`at4ltm%JnG,yGi[UƺַGKk2Pp>J;TR-!1?B/RvZ2`h$%NzW<4n(k1=?lkV隒7YE(̐ 2 1GU c+Eh+ i<- Ry5YQď GX&:WrxNW Gf 16-k[bj:i8W+G Rz}kC Υ퇞~:" ]3bm ӼbbZHq82hh&`VU [\Rr 0b)Ouۭ_uHSh"{hKnU"\ g3NR+"ĺIr,~WRd ;Z@ߩ4)!A]1M{wMע;*G#Q5N֮,SFpCӐ7.rޣ.4S4}wEN69̫Yw'[U\?ӯ_#U4oLbrM0n;ӿ;MSi>W9ӗu 踕cW:+H:o:ڍmT\F\X!%ǟ1nZZt[J[m3ݲ;dQ\;#rax[.7 JyAZkeH:YҐvS6D8(G`G'l+Jͧo'aOGpXd+zJMEӔ!.)ggZDaJ\㽥^-#C9Kf|r7KNZ528xR!7꾜I?_WtZXk \?0:FM[~m[Ҫv6R )+;>΍LJ4ʼnK~W-:0腫HcUke"YikZ8UrE,ɥȠdP2(9nzRy(\rXG·vb8!8;E}l<^=xޥxdԝv U(!/U3Bzzr‚˗.\ǖ1; T}BXEġT4rSS000000.SIT6SITUFILE06\ :7/ \ :7/,BA?Definito dall'utente m-DT!?At¹=#1*BrDM>B,їD{;4i?WDK?i$f?,u_?iQ¯Wꀹ[_?l????F'pB<7F'>?pn Y>Ȕ75<?kRSZʑ?C쿱2Ȍ ٿL?_bt?/\{)()+Ŀ3\i~1a1 stP~~A?@c,?frecciaverde.jpgCJFIFHHCC "  *  !&BEac"  ?h,4n?Ok9fk<"Trpd>9\SH9\#Bs+jZ׊Z v}u9峻cHV?Sx8FCD=E55_{r[5 6Ъ(P؞Mkc`csF=^~ǝYa>35V1h,5w_`m`xXx""p=yU[mq9\SH9\#Bs+jZ׊Z v}u9峻cHV?Sx8FCD=E55_{r[5 6Ъ(P؞Mkc`csF=^~ǝYa>35V1h,5w_`m`xXx""p=yU[mqB,їD{;4i?WDK?i$f?,u_?iQ¯Wꀹ[_?l???\Cb?Jt?TT ?JGtB?h,¤yV ^# "[N{?t@?b,?Iƿ8,?Vĥk>~XM?0KA?a俓?L<3?1a1 s4.x=!uBAdA%=D!,BA_W5=  BAmEƧ= BA5U=u `PBA4e=0 BA!u=BAG.=@tBA+ѕH=`*BAGb=BAX|= BA떨=NBA!#=J`BAL6ʨ=BAK=rBA<`=z@)BAUs=4߾BA1& 3=BAV6(M= MBAF1g=cBAV9=`BA]fB=qBAvJ='BA(Sϩ=L@BAM[=BA!'d=KBAK<l=z BA$Qt7=4BATc}Q=`oBAXvk=&BA=aBA=@BAS=IBA'Ӫ=BA:7=H BA\G=mBA<X!=`$BA[h;=tBA(xU=.BA`=o=@HBA[Oމ=BAb棫=ZBA!v= lBAL׫="BA*=`BAU =?BA &=FBAH@=@BAWZ=jBA (%t=#jBA9,= !BAU%I4=BAHIP 87937tPNϢA?@c,?frecciaverde.jpgCJFIFHHCC "  *  !&BEac"  ?h,4n?Ok9fk<"Trpd>9\SH9\#Bs+jZ׊Z v}u9峻cHV?Sx8FCD=E55_{r[5 6Ъ(P؞Mkc`csF=^~ǝYa>35V1h,5w_`m`xXx""p=yU[mq9\SH9\#Bs+jZ׊Z v}u9峻cHV?Sx8FCD=E55_{r[5 6Ъ(P؞Mkc`csF=^~ǝYa>35V1h,5w_`m`xXx""p=yU[mqB,їD{;4i?WDK?i$f?,u_?iQ¯Wꀹ[_?l???\Cb?Jt?TT ?JGtB?h,¤yV ^# "[N{?t@?b,?Iƿ8,?Vĥk>~XM?0KA?a俓?L<3?1a1 sS6Nq? "=4.x=!uBAdA%=D!,BA_W5=  BAmEƧ= BA5U=u `PBA4e=0 BA!u=BAG.=@tBA+ѕH=`*BAGb=BAX|= BA떨=NBA!#=J`BAL6ʨ=BAK=rBA<`=z@)BAUs=4߾BA1& 3=BAV6(M= MBAF1g=cBAV9=`BA]fB=qBAvJ='BA(Sϩ=L@BAM[=BA!'d=KBAK<l=z BA$Qt7=4BATc}Q=`oBAXvk=&BA=aBA=@BAS=IBA'Ӫ=BA:7=H BA\G=mBA<X!=`$BA[h;=tBA(xU=.BA`=o=@HBA[Oމ=BAb棫=ZBA!v= lBAL׫="BA*=`BAU =?BA &=FBAH@=@BAWZ=jBA (%t=#jBA9,= !BAU%I4=BAHIP 87937tPNϢA?@c,?frecciaverde.jpgCJFIFHHCC "  *  !&BEac"  ?h,4n?Ok9fk<"Trpd>9\SH9\#Bs+jZ׊Z v}u9峻cHV?Sx8FCD=E55_{r[5 6Ъ(P؞Mkc`csF=^~ǝYa>35V1h,5w_`m`xXx""p=yU[mq9\SH9\#Bs+jZ׊Z v}u9峻cHV?Sx8FCD=E55_{r[5 6Ъ(P؞Mkc`csF=^~ǝYa>35V1h,5w_`m`xXx""p=yU[mq?pn Y>Ȕ75<?kRSZʑ?W{gW]?~?Yÿ} L2?o.mCrΊq ?ׂvp?Ȳ_ڞ?SaD]?1a1 s^NϢA?@ugnH? SS000024.SIT]SITUFILE064\ :7/4 4\ :7/BA@@Definito dall'utente m-DT!?A*[ea?+hRWy^S0?<\ԇҬ\J'?P?L}ǿXlҿs ????1Ҭ?_ {?ӻ?Չ6烿{?j^#M̡ꖿUX)??@0۾?|-|h鿽7q?3^a?#?'?zq?1a1 sf?Bpp?puBAf?mCpp?p,BA>?6Dpp?p BA?Epp?pBA?Epp?p`PBA?Fupp?pBA?vGbpp?pBA?JHOpp?p@tBA?I;pp?p*BA?I'pp?pBA?Jpp?p BA?Kop?pNBA?xLop?p`BA?NMop?pBA:?$Nop?prBA\?Nop?p@)BA?Oop?p߾BA?P}op?pBA?yQfop?p MBA?MRPop?pBAH? S:op?p`BA?S#op?pqBA?T op?p'BA ?Unp?p@BAT?eVnp?pBA?3Wnp?pKBA?Xnp?p BAL?Xnp?pBA?Ynp?p`oBA ?aZmnp?p&BAn?([Vnp?pBA?[?np?p@BAI?\)np?pIBA?r]np?pBA9?0^mp?p BA?^mp?pmBA@?_mp?p`$BA?X`mp?pBA`?amp?pBA?amp?p@HBA?Sb{mp?pBA??bgmp?pBA?cVmp?p lBA?dFmp?p"BA#?zd9mp?p`BA?d/mp?pBA?Ze(mp?pFBA?e!mp?p@BA?{fmp?pBAh?)g mp?pjBA6?glp?p !BA?hlp?pBA?lilp?p`BA?8jlp?pEBA?klp?pBA?klp?p@BA?llp?phBAw?mlp?pBAt?Tnrlp?p BAw?*o^lp?pBA?pIlp?p`CBA?p4lp?pBA?qlp?pBA?r lp?p@gBAտ?Yskp?pBA?/tkp?pBA?ukp?p BAF?ukp?pABAu?vkp?p`BA?wkp?pBA?Uxpkp?peBA?(yZkp?p@BA\?yCkp?pBA?z,kp?pBA?{kp?p @BA8?i|jp?pBA?6}jp?p`BA?~jp?pdBA=?~jp?pBA?jp?p@BA?^jp?pBAl?$ujp?p>BAܲ?灓_jp?p BAP?Hjp?pBA˱?g1jp?p`bBAK?#jp?pBAѰ?ۄjp?pBA]?ip?p@BA??ip?p?pn Y>Ȕ75<?kRSZʑ?W{gW]?~?Yÿ} L2?o.mCrΊq ?ׂvp?Ȳ_ڞ?SaD]?1a1 sENϢA?@v3B4?SS000035.SITSITUFILE06\ :7/ \ :7/,BA?Definito dall'utente m-DT!?AkLa??pn Y>Ȕ75<?kRSZʑ?W{gW]?~?Yÿ} L2?o.mCrΊq ?ׂvp?Ȳ_ڞ?SaD]?1a1 s4g?E1pp?RuBA?Fpp?R,BAE?FGop?R BA?Gop?RBA?gHop?R`PBA?Hop?RBA?mIop?RBA?Iop?R@tBA?eJmop?R*BA?J\op?RBA?VKLop?R BA?K=op?RNBA??DL.op?R`BA?L!op?RBA{?2Mop?RrBA?Mop?R@)BA?$Nnp?R߾BA?Nnp?RBAL?Onp?R MBA?Onp?RBA?Pnp?R`BA?Pnp?RqBAG?"Qnp?R'BAe?Qnp?R@BAu?4Rnp?RBAx?Rnp?RKBAm?TSnp?R BAU?Snp?RBA.?Tnp?R`oBA?"U|np?R&BA?Usnp?RBAb?pVjnp?R@BA?Wanp?RIBA?WWnp?RBA ?XMnp?R BAt?^YCnp?RmBA?0Z8np?R`$BA?[,np?RBAE?[np?RBAd?\np?R@HBAp? ^mp?RBAm?5_mp?RBA`?~`mp?R lBA\?amp?R"BA?cmp?R`BA"?5e\mp?RBAv?f$mp?RFBAw?Chlp?R@BA?jilp?RBA\?\jlp?RjBA?*kilp?R !BA\?kGlp?RBAHD 489154?Bpp?puBAf?mCpp?p,BA>?6Dpp?p BA?Epp?pBA?Epp?p`PBA?Fupp?pBA?vGbpp?pBA?JHOpp?p@tBA?I;pp?p*BA?I'pp?pBA?Jpp?p BA?Kop?pNBA?xLop?p`BA?NMop?pBA:?$Nop?prBA\?Nop?p@)BA?Oop?p߾BA?P}op?pBA?yQfop?p MBA?MRPop?pBAH? S:op?p`BA?S#op?pqBA?T op?p'BA ?Unp?p@BAT?eVnp?pBA?3Wnp?pKBA?Xnp?p BAL?Xnp?pBA?Ynp?p`oBA ?aZmnp?p&BAn?([Vnp?pBA?[?np?p@BAI?\)np?pIBA?r]np?pBA9?0^mp?p BA?^mp?pmBA@?_mp?p`$BA?X`mp?pBA`?amp?pBA?amp?p@HBA?Sb{mp?pBA??bgmp?pBA?cVmp?p lBA?dFmp?p"BA#?zd9mp?p`BA?d/mp?pBA?Ze(mp?pFBA?e!mp?p@BA?{fmp?pBAh?)g mp?pjBA6?glp?p !BA?hlp?pBASiriusENϢA?@v3B4?SS000038.SIT6SITUFILE06\:7/\:7/BA@@Gz?Definito dall'utente m-DT!?Aɗ[a?O]fJcKu ?nԬǥ?3?g%Mǿy/Biҿ- ????7?]qrlBQ?h;fc?[EXBQ{?IC;z⾚5ިcn2^>>!?1-04?ȳ?O/tu^uz?#YM翺@rV?yYj?>L]&_?uA"I?1a1 spNϢA?@uЪ ?1_bilancia.jpgJFIFCreated with The GIMPC   (1#%(:3=<9387@H\N@DWE78PmQW_bghg>Mqypdx\egc "M  !R1AQ"Uaq#$25t&STr4B%36Vcds?H`ql'Ukdqs0^aWNUR{6nm*u[*Vw`\W&P*Aө(K-EemlܜUj&I8c14nkNUR{z7m6nG,M#WҞ:JhA%Ͽeꄭn[ͧ*S^9br1Y:ZkһܻX=mTJ>{K[;ַb޾*J"[wݿw6'ovʘ7t^ӥ5$_z,:WQ&[wKm)m񶱩suN*U=|Y֭:%9Oy$1LNvVujw-9d1ʊJkuĹ?@ Ta)=^v^mtM*ouct7߽R++x҃KiAcu ;$U7sG\㭧}i^ݖp{f[~Q*Q7"5f[:Vjq|v}Ć6oSTMS<VֶB݄~e~Oo{lb] vT)p>Kfo>UVwmo[o_!Jyzkt)2%}]_Š/2Sz:)qr[tfLo#9UGJdړ/IoȤsG-^Ww?ZSfcםY,|pJs': ?1j;LvRsڝljOЙXdkjS.sO($0dJ{˟Q[FTfR*&[o#FVHNkM8\.dTK&}lk**MW_:=ŧr-9"i2$5ܣ-Yy>- WvђkL6?/K"? m.-5%d !'18wO.2Xtܸ0fȯDL"rGXNC?BC?GZS=U~⚒Q II! (˧%`ʸR .6JSPKt>_"Xt_W >ȧkީoPH`?oyȓT+vjJ 4w +UNkXTIneGѫ|`۟' ȿt%J2{reeѪM I~9?-%Fd ]9&rMsE(C&T:If{1x)Cibj=5sҌ,3J %Ld3S#wR{:?Y)#\X;rϾzV0c-ٻo#05-僺K DZNSM`V%p73Iw5Ujnܰ1+޷=5Y*pW-/GmK%[RI\uO y'_kS+7g޷n0g=}*M퀮כ{M|A[i+}rC-5oH9.\'Oshd4KΣpъ (8;?ˏ-5oH{妾 O)Hw# %w瀮w Zg~X |r;Siao#/DkGKp{Lrk<ߖ߾H<ߖ_-܌{妾 -).\5⍕rqy1l wϖrk$=_V䇾Zk \M|A[6GLl5ףk3i`WM|A[:PizR֍JrR\,?ox漪cWE1tIG$rU}-ӕ9b8;K~h{YO]C~xvWI Mi{b]GǐFtݸ.2K}"X}#sY֣:nFnQMm3Jt&Z|"jۧ=&_#^ t-.g8[ՔzFߐ^oy6%cwֵzl.m*U"$4k.8%_K~]/pK t.8%_K~]/pK t.8%_K~]/pK t.8%_K-wM& _K~]/pK t.8%_K~]/pwt.8%_lKs|(I# tI﷝3=qnמ.v`z8=%bZ>j^F;/n5n5 v;.ڦkoE]b_ 6g{Go=6bZ4h3MkѶyfzm}W׹_-ʊgٞ_Uhg{Go=6;}^Mfzm}Wv3k꽣ٞ_Uhg{Go=6;}^Mfzm}Wv3k꽣ٞ_Uhg{Go=6suUXKN{xy maN]&uZ.fߑL{KeD Mfzm}W^'NQ}TwOיxEFW$L3k꽣ٞ_UijVvWEQNJog@*#NrRZdceG\m~mPcMc3kU3]%@ [-+mUܿT/*Vm̾X4ehпV&8T*UgNkiAh[8-odI*}iP=.~kQqvyD?-o/qޒ_̒զב-c˗C军W\zKE4݃o ߫qw/K12gɵJO+A<^8ѩ/)I_>_3}(ޥ+z+zfYzv,64˾ms~{*4o_Lgx2HrQeNo7۽5LWԸ{Vq)'q.o8o/jTO hfgh+>2=vڳemuF*1ٮ{8